Small Mammals - Ferrets Flashcards
What is the taxonomy of ferrets?
o Phylum: Chordata
o Class: Mammalia
o Order: Carnivora
o Family: Mustelidae (weasel, skunk, badger)
o Genus: Mustela
o Species: putorius furo
What are the names of female, male, vasectomised male and baby ferret?
Neutered male and Neutered female
- female - Jill
- Male - Hob
- Hoblet
Baby- kitten or pup - Gib=Neutered male
- Sprite=Neutered female
What is the lifespan and weight?
- 6-9 years
2. 0.6 - 2 kg females are 600 - 1.5 kg
Talk about the glands of ferrets
- No sweat glands - prone to overheating
- Sebaceous Glands - found all over body, high density around mouth and anus - odour
- Anal Glands - well developed
Describe the spinal vertebrae
C7 T15 L5 S3 Cd18
Feet
5 toes
What is interesting about the zygomatic bones
- unclosed - open orbit like the dog
Ferret dentition formula
I 3/3 C 1/1 PM 3/3 M 1/2 = 34
What type of dentition do ferrets have?
Brachydont dentition - short crown and well-developed roots that contain a narrow pulp canal.
Name the paired glands of the ferret to do with the digestive system
o Submandibular o Parotid o Sublingual o Molar o Zygomatic
When does digestion in the ferret begin?
- don’t really chew
- Likely saliva is for lubrication rather than digestion
- no amylase activity in the parotid or submandibular
- digestion therefore doesn’t start until reaches stomach
What is the nerve supply to the salivary gland?
- Sympathetic – cranial cervical ganglion
2. Parasympathetic – facial, glossopharyngeal or trigeminal
Stomach
• Simple stomached
2. Stomach is large and capable of enormous distension and allows gorging
o Can hold 50ml/kg or more
3. Secreted HCL even when not fed - inc acid, bad!
• No true gastro-oesophageal sphincter
o Therefore, they CAN VOMIT
o Often regurgitate food
What happens if starve and surgery
- Ferrets have a rapid intestinal transit time so you don’t have to starve for long periods (2-3 hrs before surgery)
- If starve too earyl they suffer with hypothermia and hypoglycaemia
What sort of eaters are ferrets and what is the best ratio of foods?
- obligate carnivores - lack ability to digest fibre
- high protein diet 34-40%, 20% fat and 25% carb
- Over 4 % ferrets have issues with malnutrition. Results in gastro intestinal issues and diarrhoea
What is the oesophagus like? how is this similar and different to other species?
- like DOG striated muscle THROUGHOUT length
2. Cat has smooth muscle for the last 1/3 rd
Small intestine
• Small intestine – approx 190cm long
o Duodenum
o Jejunum, Ileum (jejunoileum)
o Ends at ascending colon (no cecum, no distinct junction between SI and colon and no ileocolic valve
Large intestine
• Large intestine – approx 10cm long
o Ascending, transverse, descending colon
Respiratory system
- NOT obligate nasal breathers, but do preferentially use this route
- Pant if too hot
- Long narrow thoracic cavity
- Lungs have a large volume relative to body size (oppo in rabbit)
- Left lung has 2 lobes, cranial and caudal
- Right lung has 4 lobes: cranial, middle, accessory, causal
Tubing is difficult if want to feed artificially so what?
Oesophagostomy tube better choice
To listen to the heart
- Auscultated more caudally than dog or cat, 6-8 rib space
In dog heart between ribs 3 and 6 LHS: Pulmonic valve = rib space 3 Aortic = 4 and dorsally Mitral = 5
RHS:
Tricuspid = and in spaces 4 or 5
Usual respiratory rate
30-40 breaths pm
What is the resting heart rate
o 180-250bpm
How do we assess cardiovascular performance in ferrets?
o Pulse pressure
o Pulse not reliably palpable in ferrets
o Urine output -Used as an indirect measurement of cardiac output (how much blood pumping and how hard kidneys working)
What is ferret blood volume as a % of body weight!
5-7% of body weight
If youre doing serial blood samples on ferrets what % can you not exceed and in what time period and why?
no more than 15% of total blood volume extracted over 28days in order so can regenerate
What is their PCV
high! up to 61% can be normal! (would expect 30-50% in dogs and cats!)
Blood transfusion?
YES
Don’t need to cross match
severe cases of post oestrus anaemia need a BT
Where do you blood sample from?
o Cephalic vein, front leg
o Jugular vein
o Tail artery may be used in laboratory animals (don’t use in practise as others easier)
How do we sex ferrets
- Obvious size difference
- Males - testes and penis obvious
- Preputial opening on abdomen is a lot further forward than might expect
- females - vulva under tail, cranial to anus
- swells considerably when in season
What age do ferrets reach puberty?
6-9 months
Urinary system broad overview
- Similar anatomy to dog and cat
- Retroperitoneal bean shaped kidneys like cat and dog
- DIFFERENT serum chemistry - C and D have inc creatinine and urea. If inc urea in ferret indicates kidney disease
- Creatinine doesn’t rise in parallel with increased urea in kindey disease
Which sex is most likely to suffer from urethral blockages and why?
What to use
MALES
- due to prostate enlargement associated with adrenal disease (most common)
- Urolithiassis, can get stones if inappropriate diet (less common)
- urinary acidifiers or alkifiers to treat - Catheterisation can be difficult due to the j shaped of penis
- Use plenty of flush, lubrication, pain relief and small diameter 3.0 or 3.5F catheter
What sort of uterus does the female ferret have?
- bicornuate Y shaped uterus
2. similar to bitch therefore neutering is similar too
Hob repro anatomy
- Similar to dog
- Major difference is J shaped os pnis
- Testes are small relative to body size
what type of ovulators are ferrets?
seasonal poly oestrus reflex ovulators
What season do ferrets come into season and why
- late winter, early spring
- as daylenght increases
- melatonin conc decreases
What happens if jills aren’t mated
- Failure of jill to mate results in continual high exposure to high oestrogen. This leads to bone marrow depression, anaemia & DEATH
- Thus, the female ferret, unlike other mammals, MUST be mated, or sham mated by a vasectomised (hoblet), or given chemical oestrus suppression drugs
Why can’t we just spay female ferret? And if we do spay when do we do so?
- makes them more prone to adrenal disease which is life threatening.
- If spay tend to wait for them to have a few seasons however still risk issues with hormone feedback loops
- neutering removed feedback inhibition from gonadal steroids, resulting in constant high levels of GnRH, thus high levels of LH and FSH
adrenal gland anatomy
- Lie near each kidney embedded in fat & covered by peritoneum.
- Both lie ventral to ipsilateral adrenolumbar artery so difficult to perform surgery on
- Left adrenal approx 6-8mm in length. Close to adrenolumbar vein and abdominal aorta
- Right gland 8-11 mm long. In close apposition to caudal vena cava and caudate lobe of the liver
- Blood supply from ipsilateral renal artery
What does adrenal disease in hobs and jills tend to be associated with. And not associated with?
- NOT associated with pituitary function like in dog
- Associated with:
o Neutering in males and females, especially early
o Abnormal photoperiod (i.e. animals housed indoors subject to abnormally long periods of ‘daylight’)
o Genetic component?
What are common signs of adrenal disease?
- Alopecia is a common presenting sign
- Distended belly
- Itching
- Weight loss and muscle loss
- Vulva swelling mimicking increased oestrogen hormone and male’s aggressive sexual behaviour
- Male more aggressive and female more “mothery”
- Trouble urinating as overproduction of sex steroids causes prostate to enlarge, especially for male
Why does adrenal disease occur?
• Occurs as a result of over-production of sex hormones by the adrenal glands (from zona reticularis)
- Estradiol
- Androsterone and testosterone
-17-alpha hydroxyprogesterone
• Not overproduction of corticosteroids (so different pathology to adrenal disease in the dog as dog inc)
How to prevent adrenal disease?
• Keep entire jills with a vasectomised male
-Mating results in ovulation thus reducing risk of excessive prolonged oestrogen production
• Depot injections of GnRH agonist which increases secretion for short period then overstimulation acts in negative feedback = reduced stimulation of adrenal glands.
-Reduces release of LH, and hence reduces stimulation of the adrenals
• If neutering performed, ensure ferrets are mature (can used GnRH agonist in addition to surgical sterilisation) = bit of negative feedback in hypothalamus and pituitary
• What about treatment Adrenal disease? – GnRH agonists, surgery. (papers of vital on surgical and non surgical options)
Why can’t you starve ferrets?
• Stomach – simple stomach and large, secretes HCl even when NOT fed. Inc acid production if starved
• Rapid intestinal transit time: don’t have to starve for long period (2-3 hrs before surgery.)
-Starve too early = issues with hypothermia and hypoglycaemia
